131 



nerally neglected under every zone ; it is never- 

 theless highly interesting both to agriculture in 

 the colonies and meteorology, and full as im- 

 portant as the measure of the limit of the per- 

 petual snows. My observations furnished me 

 with the data, which I shall record in the fol- 

 lowing table. 



Northern 

 latitude. 



Lowest height 

 at which the 

 snow falls. 



Inferior limit 

 of the perpe- 

 tual snows. 



Difference of the 

 two preceding 

 columns. 



Mean 

 Temperature. 





toises. 



metres. 



toises. 



metres. 



toises. 



metres. 



Cent. 



Reau. 



Oo 



2040 



3976 



2460 



4794 



420 



818 



27° 



21*6° 



20 



1550 



3020 



2360 



4598 



810 



1578 



24-5 



19-6 



40 



0 



0 



1540 



3001 



1540 



3001 



17 



13-6 



This table presents only the ordinary state of 

 nature, that is to say, the phenomena as they 

 are annually observed. Exceptions founded on 

 particular local circumstances, exist. Thus it 

 sometimes snows, though seldom, at Naples, at 

 Lisbon, and even at Malaga, consequently as 

 low as the 37th degree of latitude : and, as we 

 have just observed, snow has been seen to fall at 

 Mexico, the elevation of which is 1173 toises 

 above the level of the Ocean. This phenomenon, 

 which had not been seen for several centuries, 

 took place on the day that the Jesuits were ex- 

 pelled, and was attributed by the people to this 

 act of severity. A more striking exception was 

 found in the climate of Valladolid, the capital of 



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